The present inventive convection refrigeration process and apparatus provides for a vast improvement over existing refrigeration processes and devices which employ a refrigeration unit releasing unrestricted cold air flow to common areas of a refrigerated compartment, and/or to areas of a device which do not require refrigeration. For example, in many of the common household refrigerators using a single large food storage compartment having nominally segmented areas, for example, by sliding shelves etc., various areas are exposed to room temperature air when the refrigerator door is opened, thus immediately decreasing the temperature of such areas. The temperature of compartments which are only nominally segmented from common areas by sliding plastic or glass shelves and the like, and are typically not air tight, is also lowered by exposure to room temperature air. Such conventional refrigerators are thus very inefficient as large amounts of energy are expended to attain the desired cooling temperature upon shutting a main door common to all refrigerated areas. Maintenance of different temperatures in different refrigerated compartments is also typically not possible.
An improvement upon the standard refrigerator is disclosed in U.S. Pat. No. 4,662,186 to Park. In this reference, a refrigeration apparatus is discussed which comprises a housing having a food storage compartment with a food storage drawer slidably disposed in the food storage compartment. The apparatus also utilizes an air delivery duct for directing a stream of chilled air to the food storage compartment which also includes a chilled air delivery vent in the drawer and a return air duct for returning air from the food storage compartment in a return vent opening in the compartment to a chilled air generating means. Also included is a means for automatically blocking the flow of air through the delivery vent opening and return vent opening when the drawer is in an open position, and for automatically unblocking the flow of air through the delivery vent opening and the return vent opening when the drawer is in a closed position. The vent blocking is performed by a system of dampers operated by push rods mounted on the drawer, such that when the drawer is closed, a damper moves an air vent to an open position, and when the drawer is opened, the damper moves an air vent to a closed position. Separate sets of dampers are used for both chilled air delivery vents and return air vents.
The Park refrigerator, however, is inefficient in that chilled air from a chilled air generating means is not channeled to a specific area to maintain a desired temperature in a compartment and then returned for further cooling, but instead provides for the unrestricted flow of air throughout a housing which enters one or more drawers through the aforesaid vents, thus providing for an inefficient waste of cooling energy on areas which do not have to be chilled or maintained at a desired temperature. The mechanical venting systems of Park are also inefficient in that they are always intermittently exposed to chilled air flow and room temperature air upon opening and closing the door to the food storage compartment, and thus are prone to changes in humidity and are likely to accumulate condensate and freeze up thereby not properly closing and/or opening, thus requiring constant attention. Additionally, the Park refrigerator does not provide means for removal of water or condensate from a refrigerated compartment, nor can the Park refrigeration apparatus be defrosted without affecting the temperature in a refrigerated compartment.